Pottery machine



Mayv7, 1946. w. J. MILLER POTTERY MACHINE Filedv Jan. 15, 1940 INVENTOR WiL-[JHM rl MILLER g f ATTORNEY.

Patented Moy 7, 1946 UNITE/o STATES PATENT orrlcr.I

Pomar MACHINE William J. Miller, Swissvalo, Pa., assigner to Miller Company, Swissvale, Pa., a corporation of Pennsylvania Application January 15, 194i), Serial No. 313,861

' (Cl. 25-22l Pottery Engineering 8 Claims.

Y.l'his invention relates to the manufacture of articles of pottery ware from plastic ceramic materials, particularly vitreous and semi-vitreons ware and earthen ware in such shapes as plates, cups and saucers, bowls and the like.

This application is a continuation in part of my co-pending application for United States Letters Patent, Serial No. 205,711.

ln the manufacture of pottery ware according to the teachings of my Reissue Patent #20,- iill, the method is to automatically feed measured charges oi' clay to absorbent molds constrncted oi' plaster and bond the clay to the mold and thereafter ligger it. The step voi preforming is preferably accomplished by pressing the charge of the clay between the mold and a matrix, the clay dowing over and completely covering the molding surface Ato a depth greater than in the nnlshed piece, the excess being 'removed by the prole. i t

Onefobject of 'this invention is to provide for rapid and automatic exchange of preforming lnstrumentalities in correct working position, without interrupting production; another object is to selectively enable each'exchange after a predetermined number of pieces of ware in each shape has been produced.

The invention comprehends the combining of a press as herein disclosed with either feeding or ,iiggering mechanism or both in a single unit or the press may be set up and operated alone.

@ne advantageous feature is that the dilerent pieces in a tableware set may be made atv high speed, in succession and with a single unitary apparatus. Another advantageous feature is that manual intervention is eliminated entirely or considerably minimized and speeded up in the matter of exchanging preforming implements in working position. Still another advantageous feature is that the operating mechanism is simple and fool proof. It is particularly advantageous for small size potteries or potterles catering to small lot diversiiled shape production such as hotel dinnerware and high quality vltrified dinnerware.

in the drawing,

Fig. l is a. sectional elevation of a preforming machine mounting a plurality ofdiversiiied preforming implements which are'- exchanged manually. v.

Fig. 2 is a top plan view oi' a bayonet type locking mounting for the press mold chuck of Fig. 1.

Figs. 3 and 4 illustrate respectively a cross section and topv plan view if a preforming die and releasable securing mec anlsm whereby said die may be 'quickly and easily removed and enchanged 'by hand.

Fig. 5 is a view with certain of the parts in section 1ci a plural head preformer support and mechanism for automatically exchanging preforming implements inthe working position.

Fig. 6 is an end view looking in the direction oi line -t of Fig. 5.

Fig. 7 is a detail illustrating how the operation of the actuating mechanism for the apparatus vof Fig. 5 may be controlled by the mold conveyor.' v

`Fig.. 8 is adetail partly in section disclosing means for supporting the preiormlng implements i fn' horizontal movement into the working posit on.

With reference to Fig. l, the preforming apparatus disclosed therein is iorl the manual exchange of preforming implements at the Worhing position and comprises, generally, a rotatable turret i on which a multiple of diverse hollow Ware and flat ware preforming implements in the form of dies l, 3 and t are mounted, said dies having molding surfaces reversely contoured to that oi' the mold adapted to co-operate therewith..y 'Ihese dies are alterable at the worlrlng position and are adapted to co-operate with molds supported by a chucl: t which is adjustably and removably secured to a pedestal secured to a vertically reciprocable crosshead t raised and lowered by a cam t. v

The mold chuck t is constructed according to teachings oi. my co-pending application, Serial No. 205,711, being adapted to support and reinforce the mold during periods of applied pressure. Said chuck comprises a rigid shell lll having a. liner `il composed of a material as specifled in my application just mentioned, said material being molded to the shape oi the side and bottom of the mold but sumciently oversize to enable easy insertion and withdrawal of the mold.

When pressure is applied, the material, which is confined to the rigid shell lll, swells out in the zone of the side wall of the mold and intimately engages the same. Rubber is a suitable material.

The chuck 6 has a socketed base provided with radial lugs 43 extending into the socket portion. These lugs form one part of a bayonet type lock by means of which the chuck is secured to the head 'of a'sleeve I2. The head of the sleeve is cutaway at opposite sides to allow the lugs to fit on over the head, there being .undercut grooves M into which the lugs pass upon rotation of the chuck a 4quarter turn in either direction to thereby secure the chuck in place. The sleeve d! is threaded onto a shouldered stem 40 which fits into the bore of a pedestal d@ mounted on the crosshead 5, a shoulder positioning the altitude. `A set screw d3' prevents accidental displacement of the adjusted position of the sleeve d2.

With the arrangement just described, chucks may be quickly and easily replaced either by removing the entire assembly from the pedestal or by detaching the chuck 8 and exchanging it for another. If the adjustment of parts of the assembly is not disturbed when removed from the pedestal 48, it may be replaced at any subsequent turn without need for resetting. Several of these units may be kept on hand.' each preadjusted. to fit and support in the proper elevation various types of molds.

' A suction duct 50 is provided to apply suction to the mold to insure reliable gripping thereof in the chuck when the mold and clay blank are parted from the die. The duct l@ may be connected to a source of an air under pressure, both controlled by a valve which alternately applies suction to secure and pressure to release the mold from the chuck.

For mounting the dies, there is disclosed at i a rotatable turret having trunnions 52 which are journaled in supports 53 secured to columns 54. The turret has a multiple of faces and each face B has a llarge central opening to permit vertical displacement of the die base be. The die is Y attached to the base by screws B1 and said base is threaded into an adjusting ring 58 concentric with the opening and rotatably supported by asco,

members Bs. .This arrangement simplifies vertical adjustment of the die which can be made whilst the machine is in operation.

The die 2 is for making hollow ware and 3 and t for making ilat ware. When changing from flat to hollow ware and vice versa, the chucks may be subject to exchange, although this is not always necessary as in the case where the only difference between molds is in the contour or designlof the molding surface. I prefer that production be arranged to enable molds fitting one set of chucks to be utilized for a maximum period. I have endeavored to make the matter of chuck replacement and adjustment as economical of time and effort as possible so as not to interrupt production. unduly. The dies are quickly shifted to working position by withdrawing the indexing pin -60 from the aperture of disc 6i and rotating the turret to the desired position.

In order to secure the separation of the molding surface of the dies and the clay, thereby insuring retention of the clay by the mold, the molding surfaces of the dies are preferably rendered nonadhesive by heating the same either by steam. flame or electricity. A chambered permeable face die connected to a source of super atmosphere as per my Patent #2,079,082 may also be applied. In the case of steam. it is piped through a header 62 and branches 83 to a steam chamber in the die. there being outlet pipes 6l which convey spent fluid to a common discharge line 8B. In each line. is a valve $8 having a closure 61 operated by a lug 81a on the crosshead. When the crosshead raises. the valve is opened, thereby venting condensate into the discharge line 85.V The dies may be heated by electricity and in this case. each die is provided with a heating element 10 and connection 68. A pair of contacts 88 located adjacent the working position automatically engage contacts 8B when a die is moved into working position.` Dies may be preheated by plugging in on another circuit previously to use.

As the mold and chuck are elevated, the upper surface of the hollow ware mold engages and is gripped by a rubber stripper ring 1l contoured to correspond with the beveled brim portion of the mold. Plaster does not adhere to rubber and therefore there is no accumulation thereon after successive contacts. The mold during the pressing operation is supported and reinforced externally on substantially all surfaces by rubber to prevent mold breaking.

The rubber ring 1l is fastened to a plate lla which in turn is supported at the four comers by studs 12. being held in a depressed position by springs 13. Normally. the clay is repelled from the die, therefore, stripper ring il and vacuum in chuck cavity serve only under abnormal die surface conditions.

After the clay charge has been preformed, the mold is lowered and deposited on its briml ina transfer mechanism 14 which comprises a pair of spaced parallel bars having mold seats 13a which are divided or opened through the center longitudinally of the transfer mechanism. The seats are divided to straddle the pedestal when reciprocated. Each seat is contoured to fit a segment of the ybrim of the mold and is of heavy rubber construction to avoid injuring the brims of the mold.

It will be noted that in the intermittently actuated unidirectionally travelled exible mold carrier |02 of Fig. 5, the mold seats are not divided.

The press may be provided with an automatic clay feeder (see my co-pending application Serial No. 291,158) which segregates charges of clay and deposits said charges concentric on the molds. in which case the transfer 14 would operate in the transportation of empty molds to the feeding position and then to the press and jigger positions. Furthermore. the press may be combined in a single unitary installation with an automatic profiling mechanism which may or may not include a feeder and/or transfer.

In Figs. 3 and 4 is illustrated an arrangement for quickly exchangingindividual dies by hand. A vertical machine frame member 15 and an apertured horizontal turret or member 16 on which is pivotaliy mounted a wedge shaped latch 11 having an arcuate slot 18 enlarged at one end over the aperture. This die 19 has an upwardly projecting adjustable central attaching stud l0 circumferential ledge 8| just below the streamlined head. The stud is moved vertically into the enlarged end of the slot until the groove 8i registers with the tail of the slot whereupon the latch is forced home by the spring 8 la thereby securing the die in position. The die may be quickly and easily removed by reversing the procedure. The slightly inclined upper surface of the narrow portion engages the ledge 8| and thus elevates and binds the die against turret face. Suitable quick fluid and electric connections can be included.

Fig. 5 shows apparatus for automatically substituting another preforming die in correct working position, after a predetermined number of vpieces of one pattern has been made.

The apparatus. comprises a turret 82 similar to that shown in Fig. l on which are mounted a plurality of dies. The turret is mounted on trunnions 83 journaled in the machine frame and is rotated by means of a four point ratchet wheel 84 keyed on the turret and a reciprocating pawl 85 with apertures in unindexingr plate Il by spring 9|) and piston lla of air cylinder I'Ia to intermittently lock the turret in working position. Conduits I9 through valve "a conduct compressed air to the cylinders. An operating lever 94 provided with a return spring Il controls the opening and closing of the valve which is operated either by trips It. Fig.5, removably secured to various mold carriers 91 carried by an endless chain conveyor, said conveyor being preferably as disclosed in my Patent #1,856,498-or by the spider |03 of Geneva mechanism which determines valve operation intervals.

When lever u is shifted by trip Il, air enters below piston 90a to withdraw index pin l1 and also above piston a to rotate turret 82 one station. and when lever M slips ofi trip 86. air

escapes from both cylinders to permit spring i0 to first extend index pin and then spring lib t0 retract the pawl I5. Relative operation precedence is established through adjustable valve 9| or adjustable'valves in the fluid lines and/or relative area of pistons or resistance of springs tub and du.

Conveyor iti is an endless chain preferably travelling for a portion of its length in a dryer and has a pluralityof spaced open bottom mold carriers, which are preferably surfaced with a shoch absorbent or cushioning material such as rubber or "spauldite to minimise abrasive action be tween the molds and the otherwise metallic seatsA of the mold carriers, in which are disposed. in the duction is made. Cam lili on shaft 9B raises and lowers crosshead tit and chuck lill). The conveyor i tt is synchronized with the operation of the cam so that it will advance a distance equal to the center to center spacing between carriers when the chuclr. is in the lowermost position. this being in accordance with the teachings of my United States Patent #1,356,498. y

A Geneva spider tilt mounted on shaft Wt and having radial slots itt is intermittently rotated by a cranls member itt mounted on shaft imv and driven from shaft di by chain illl and sprockets itt. it roll iii! pivotaliy connected to the end of rotary member itt intermittently enters slots itt to thereby rotate the Geneva one spacing during a portion of each revolution of the main shaft tt.

The Geneva has a ring of spaced holes i i i equal to the number of slots lub and removable pins itt are positioned therein for operating the valve lever it. The number o radial slots lying between pins determines the number of pieces of ware produced between tool changes. If desired, all pins may be removed and the press operated exclusively on one shape. In other words, the movement of the pins il? is synchronous with the movement of the molds on conveyor |02 and into fabricating position.

l order desired, the various molds in which the prov3 By virtue the tool shifting mechanism herein and the control apparatus therefor, it is possiblev `to shift the proper' tool into fabricating position automatically incident to the approach of a Dredetermined mold tothe fabricating position. The control mechanism not only synchronizes with the main shaft ,of the fabricating machine but also with the mold.

Any number of pieces of ware of a particular shape may be made and the production changea to 'another shape without manual intervention. unless it is necessary to change the chuck and this may be obviated by mounting the chucks on a turret and revolving said turret in the same fashion as the die turret is revolved.

Having thus described my invention, what I claim is:

1. In apparatus for manufacturing pottery ware, the combination of means for forming pottery ware and means for undersupporting plaster molds at the forming. position comprising a rigid container having a molded insert of resilient material shaped to nt the bottom and sides oi.' a mold together with means for oversupporting the mold comprising a resilient body enggeable with the upper surface of the mold, said mold being gripped in a resilient embrace, top, bottom and sides incident to the performance of the fabricating operation whereby breahage of the mold is prevented by any vibratory action imparted to various parts thereof during said operation. 2. in apparatus lor manufacturing mttery were, means for supporting plaster molds incident to the fabricating oi' ware engageable with the top, bottom and sides of the mold including a cushioning material capable of conforming temporarily thereto to absorb any vibration imparted to all parts thereof during operation of the apparatus.

3. A pottery machine having a number of pressing dies exchangeable at a. given forming position and means enabling the rapid exchange of dies at said position comprising indexing means rotatable about an axis, a mold chuck and a chuck support Fig. 7 illustrates how the valve may be operated by means or the mold carrier i02. A striker arm tt is adjustably secured to a mold tray containing the initial mold or molds signifying a change in production and requiring a change of dies. The arm 96 will engage and throw the valve lever 94 prior to the mold coming to rest under die 2, thereby setting the exchange mechanism in operation.

Fig. discloses an arrangement wherein the dies ymay be mounted for movement in a horizontal plane into and out of the working position. The apparatus consists of a turret I I5 mounted on a vertical shaft H8 and may be rotated by hand or mechanically as shown in Fig. 'l'. The chuck lll indicates the working position.

having interiitting connections with the mold clinch fully engageable or releasable by partial rotation of the chuck and holder relative to one.

another.

ii. The combination with a pressing die for pressing out clay on the molding surface of a plaster mold and a registering mold chuck for receiving and supporting molds on which clay is pressed out by the die of a mold transporting andindexing means having several mold seats from which molds are lifted therefrom and replaced thereon by the chuck, said mold seats being composed, at least in part, of a cushioning material such as rubber or the like on which the molds rest when supported thereby.

5. The combination with a forming tool for forming pottery ware on the molding surface of a plaster pottery moldand a registering mold chuck for supporting molds whilst clay is being formed thereon of a support for the mold chuck enabling quick exchange and replacement of mold chucks comprising a hollow pedestal and a member having a sliding fit therein fromwhich 4the member may be pulled. said member being cornposed of parts that are adjustable to vary the vertical positlon of the mold chuck above the pedestal.

6. `The combination with mold indexing means for presenting plaster molds at a forming position of a die support. manually rotatable about a horizontal axis. mounted above said mold indexing 4 l ascenso means. a plurality et non-adhesive dies for making ware of different size or type detachably secured to said support, and indexing means for loeating and locking selected dies at the forming position.

7. A pottery machine having a plurality o! ware fabricating tools arranxed to be alternately sub- A stituted for one another at a given fabricating position, mold indexing means, and iiuid operated mechanism controlled by the mold indexing means for automatically shitting the tools into and out .of the fabricating position.

10 mold indexing means.

WILLIAM J.'MII1ER. 

